1. Field of the Invention
The present invention relates to novel bisphenol-derived, hydrocarbon-stabilizing agents. More particularly, it pertains to new oligomeric bisphenol derivatives, characterized by certain terminal groups, which are useful in stabilizing a wide variety of hydrocarbon polymeric materials which are subject to oxidative and ultraviolet (UV) degradations.
2. Description of the Prior Art
Most hydrocarbon polymeric materials, e.g., polyolefins, elastomers, engine fuels, waxes, lube oils and the like, are known to have oxidation or thermal degradation problems caused by the chain reaction among polymeric free radicals formed within the matrices. It has been theorized that free hydrogen radicals can react to trap the polymeric free radicals, thus stopping the chain reaction. Accordingly, most oxidation stabilizers derived from phenol or bisphenol compounds generally contain free terminal hydroxyl groups, i.e., --OH groups directly attached to phenyl rings, which can donate the hydrogen radicals needed to retard the oxidative degradation as mentioned above. Although said stabilizers containing free hydroxyl groups such as those disclosed in U.S. Pat. No. 3,510,507 (Bown et al.; 1970) are generally acceptable antioxidants, their stabilizing efficiency sometimes diminishes due to the interaction between the free hydroxyl groups and certain acid, base or metallic ions released from various sources, e.g., containers. Such loss of antioxidative effectiveness is often evidenced by early color developing in the matrices where said stabilizers have been added.